Size comparison with a cigarette pack

Oh my.. look at this thing.. it's not a coat hanger, you know..;

The front skirts can be made to move individually with a simple mod — but...
Once you cut them, they end up flopping around pretty badly;
It doesn't seem like much thought went into keeping them secure after splitting...
If you don't like loose front skirts, don't bother splitting them.

The side skirts, which clip onto the hip joint via ball joints, are also a bit loose and tend to pop off easily.

The backpack verniers, held in place by large ball-shaped polycaps, are also weirdly loose;;
For parts connected via ball joints, they rattle around to an almost baffling degree.

On the plus side, the rifle and palm have a peg-and-slot system, so grip strength is no issue at all.

Being a transforming kit, the legs fold up nicely.

First off, the ReZEL uses a parts-swap transformation rather than a full transformation.
You'll need the transformation body and connector parts shown above to pull it off.

Start by removing the chest armor and backpack from the upper body, then boldly set the torso aside... (-__-)

For the lower body, disassemble the legs, hip joints, side skirts, and so on.

Plug the lower body — with the front and rear skirts attached — into the back.

Fold the feet and legs up completely,

Then plug the backpack on top...

After transformation, you're left with the upper torso and hip joint parts.

For displaying the Waverider mode on a stand, the manual recommends Action Base 1 over Action Base 2.
That's because you'll need the long fixing pin that comes with Action Base 1.

Underside view.
Somehow the underside looks even cooler...

In terms of lore, the ReZEL is basically a mashup of the Gejan and the Re-GZ.

Together with the HGUC Unicorn lineup.

Together with the Kshatriya and Geara Zulu.